What is a mammogram?
A mammogram is a low dose X-ray of the breast tissue. Mammography is performed to look for early signs of breast cancer before a patient develops symptoms. It can also be used to look for any abnormality when a patient develops a new symptom (a lump or focal pain) in her/his breast tissue.
A routine screening mammogram usually includes at least two pictures of each breast taken at different angles, typically from top to bottom and from side to side. When a mammogram is viewed, breast tissue appears white and opaque (cloudy), and fatty tissue appears darker and translucent (semitransparent).
Screening mammograms are recommended every year for all women starting at age 40. Screening mammograms are also done for women who have no signs or symptoms related to the breasts (asymptomatic).
If there is an abnormality or patients have a new symptom (a lump or focal pain), additional evaluation may be needed. With further examination, most of these questionable abnormalities are found to be normal breast tissue or benign (non-cancerous) tissue.
How often are abnormalities found in a screening mammogram?
Potential abnormalities are found in 6 to 8 percent of women who have screening mammograms. This small group of women needs further evaluation that might include breast physical examination, diagnostic mammography, breast ultrasound, or needle biopsy.
After this additional evaluation is complete, most women who have potential abnormalities on a screening mammogram are found to have nothing wrong.
How does an abnormality appear on a mammogram?
A potential abnormality on a mammogram might be called a nodule, mass, lump, density, or distortion:
- A mass (lump) with a smooth, well-defined border is often benign.
- Ultrasound is needed to see and describe the inside of a mass. If the mass contains fluid, it is called a cyst.
- A mass (lump) that has an irregular border or a starburst appearance (spiculated) might be cancerous, and a biopsy is usually recommended.
Microcalcifications (small deposits of calcium) are another type of abnormality. They can be classified as benign, suspicious, or indeterminate. Most microcalcifications are benign. Depending on how the microcalcifications appear on the additional studies (magnification views), a biopsy might be recommended.
What are the different types of mammograms?
There are two common types of mammograms:
- Diagnostic Mammogram
- Digital Mammogram
What is a diagnostic mammogram?
Diagnostic mammograms are done for women who have potential abnormalities that have been detected on a screening mammogram. These mammograms are also done for women who have signs or symptoms related to the breasts (symptomatic). Diagnostic mammograms differ from screening mammograms in that they focus on the potential abnormality or symptom.
Depending on the potential abnormality, different studies might be done. Some women need only additional mammographic images. Other women will have additional mammographic images and an ultrasound.
What is a digital mammogram?
Digital mammograms are newer technology films that use the computer to produce the images. The equipment is very much like a digital camera and can see things better, especially in the case of dense breasts. Digital mammograms are usually recommended for dense breast tissue or for women under the age of 50. The films cannot be lost. However, the amount of compression (squeezing) and radiation is the same as with analog films.
How accurate is mammography?
Mammography is 85 percent to 90 percent accurate. Mammograms have improved the ability to detect breast abnormalities before they are large enough to be felt. However, it is possible that a mass that can be felt (palpable) might not be seen on a mammogram. Any abnormality that you feel when examining your breasts should be evaluated by your health care provider. A diagnostic mammogram might be recommended.
What happens before a mammogram?
- Follow your normal routine – it is acceptable to eat, drink and take your normal medications.
- If you are breastfeeding, pregnant or think you may be pregnant, tell your healthcare provider, as your mammogram may need to be postponed or rescheduled for a later time.
What happens on the day of the mammogram?
- Please do not bring valuables, (jewelry, credit cards) to your mammogram.
- Do not wear body powder, lotion/cream, or deodorant the day of your mammogram, as these substances can look abnormal on a mammogram.
- When you arrive, you will be asked to complete a breast history sheet.
- You will also be asked to remove all clothing and jewelry above the waist, and will be given a hospital gown to wear.
- The mammogram is performed by a registered mammography technologist, and the mammogram is interpreted (read) by a board-certified radiologist (a physician who specializes in reading X-rays).
Position of breast during mammography
What happens during the mammogram?
- The technologist will ask you to remove one breast at a time from your gown (see above), and the breast is positioned on a breast support plate. A plastic paddle will compress (squeeze) the breast against the support plate. The mammogram picture is then taken while the breast is compressed. Compression is necessary because it keeps the breast from moving (which can cause the pictures to appear blurry.) It also spreads out the breast tissue, allowing the radiologist to see through the tissue better. Finally, the least amount of radiation is used when the breast is compressed as thinly as possible.
- You may feel some discomfort or pressure during the 3- to 5-second period of compression. However, the mammogram should not be painful. If you are unable to tolerate the pressure, please let the technologist know and she/he will adjust accordingly. Compression is also more uncomfortable during some points of a woman’s menstrual cycle. To minimize discomfort, consider scheduling your appointment seven to 10 days after the start of your period.
What happens after the mammogram?
- You may have temporary skin discoloration and/or mild aching in the breast from the compression. You can take aspirin or ibuprofen (such as Advil®) to relieve the discomfort, if you are not allergic to these medications. Most women will be able to resume their normal activities immediately after their mammograms.
- Your results will be available within a few days of the test. After you receive the results, your healthcare provider will discuss everything with you and explain the radiologist’s recommendations.
Results and Follow-Up
How often should you have a mammogram?
Multiple professional organizations have made recommendations for when women should start having mammograms and how often they should screen. Although the most lives are saved when patients start screening every year beginning at age 40, the reality is the majority of women will never develop breast cancer. Therefore, it is very important women talk with their healthcare providers about their individual risk factors, and what the most appropriate screening schedule is for them.
Feel free to ask questions
If you have any questions or comments, please feel free to discuss them with your technologist, radiologist, or your regular doctor.